220 29470 <4e5c0e7e-74c1-1983-ad27-0baede6ebe0a@honermann.net> article Path: news.gmane.org!.POSTED!not-for-mail From: Tom Honermann Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Allowing string literals to match `char...` packs in templates Date: Fri, 18 Nov 2016 12:05:21 -0500 Lines: 28 Approved: news@gmane.org Message-ID: <4e5c0e7e-74c1-1983-ad27-0baede6ebe0a@honermann.net> References: <9de07b5f-f870-4a02-882f-54f9fdd12ffd@isocpp.org> <0cc57751-f41a-4da2-88e7-a42eb61f57cd@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed X-Trace: blaine.gmane.org 1479488727 19954 195.159.176.226 (18 Nov 2016 17:05:27 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 18 Nov 2016 17:05:27 +0000 (UTC) User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDBNXSHG6UDBBVHJXTAQKGQEVWHFQ4I@isocpp.org Fri Nov 18 18:05:22 2016 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-ua0-f199.google.com ([209.85.217.199]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1c7mbK-0003xA-6P for gclcip-std-proposals@m.gmane.org; Fri, 18 Nov 2016 18:05:22 +0100 Original-Received: by mail-ua0-f199.google.com with SMTP id 34sf168124081uac.6 for ; Fri, 18 Nov 2016 09:05:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isocpp-org.20150623.gappssmtp.com; s=20150623; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:x-original-sender:x-original-authentication-results :reply-to:precedence:mailing-list:list-id:x-spam-checked-in-group :list-post:list-help:list-archive:list-subscribe:list-unsubscribe; bh=pvFL5BdyQyy1cw5lJsbydD87gWztz01H51Gqt2ixYyE=; b=x/p8fkvv8AT5ZfRNrPJRy3Ag6odlly+h0iWig4oqX2u2LNmLbDXYocRFhWVNbeZVcq feeLmhLJO8BAbR6RxD4tdLZWcM4LCR2lFxOkMqBREIQl1SwnaF/SYYRtKeVFkuRNjr3J dfCbLmuk+sneN5kolQyppst1DAyQO4um05ny9aV1E45HXPoxERIQSivvseFINfsyBUjX 6IrEWjZrpZpIkDwhXr7v+QUEZ+Fenk9jHQ9BtdZLu78R8YFYzv2SuJjVWXBjGwh6w4bU E4mC/X5UHSA8dOa7NVUDw3M7Rj5tr26qbjycfZyYk60tPogXoxv3SVNEyrbCRw/MU4SF iZTA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:x-spam-checked-in-group:list-post:list-help:list-archive :list-subscribe:list-unsubscribe; bh=pvFL5BdyQyy1cw5lJsbydD87gWztz01H51Gqt2ixYyE=; b=l+PiRAt3xeDUqNjWBuCrO0+sBoDexskonSlNwZUkinecuDy7P+98uCLUvPJM8NdB7G sIs1FP2dL8JyzA1dBp8cOs8sCv2VePpKnSfoRW6ESCNZBTKZX9DS2gBa4397I/MZobXB wlDol5erW+IFR9f4/LwuaCkiLdYygDjJAh/9Qwpfg4wY2qdgMeoJ+8FrKNRs4uXk/Yp6 6sgLl26wbKMwQobpxM5zkmaR0IbmoJvcXJYGO7VS5cbSPizPunbEN5+GJjqYd23C267u em1BZy4Ibut4wW2BqASVySBiow3xbKRaOEuDhlhYEi7eoz0cutaDERnk/9OkvZKaffjJ 4RsQ== X-Gm-Message-State: AKaTC00N8vfxgwVPqRg9Pb16uh6e7gsOhNKYf+Vbxq/FLtFT78UL6J3krfyGTNoy0coJoA== X-Received: by 10.31.148.132 with SMTP id w126mr123401vkd.20.1479488725443; Fri, 18 Nov 2016 09:05:25 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.157.56.209 with SMTP id k17ls7528798ote.14.gmail; Fri, 18 Nov 2016 09:05:24 -0800 (PST) X-Received: by 10.55.134.1 with SMTP id i1mr850817qkd.219.1479488724301; Fri, 18 Nov 2016 09:05:24 -0800 (PST) Original-Received: from smtp83.iad3a.emailsrvr.com (smtp83.iad3a.emailsrvr.com. [173.203.187.83]) by mx.google.com with ESMTPS id u6si5674366qkc.182.2016.11.18.09.05.24 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 18 Nov 2016 09:05:24 -0800 (PST) Received-SPF: neutral (google.com: 173.203.187.83 is neither permitted nor denied by best guess record for domain of tom@honermann.net) client-ip=173.203.187.83; Original-Received: from smtp19.relay.iad3a.emailsrvr.com (localhost [127.0.0.1]) by smtp19.relay.iad3a.emailsrvr.com (SMTP Server) with ESMTP id 17EC45212 for ; Fri, 18 Nov 2016 12:05:24 -0500 (EST) X-Auth-ID: tom@honermann.net Original-Received: by smtp19.relay.iad3a.emailsrvr.com (Authenticated sender: tom-AT-honermann.net) with ESMTPSA id 0527A51E7 for ; Fri, 18 Nov 2016 12:05:23 -0500 (EST) X-Sender-Id: tom@honermann.net Original-Received: from [10.12.196.91] (pool-71-176-249-9.rcmdva.fios.verizon.net [71.176.249.9]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA) by 0.0.0.0:587 (trex/5.7.12); Fri, 18 Nov 2016 12:05:24 -0500 In-Reply-To: <0cc57751-f41a-4da2-88e7-a42eb61f57cd@isocpp.org> X-Original-Sender: tom@honermann.net X-Original-Authentication-Results: mx.google.com; spf=neutral (google.com: 173.203.187.83 is neither permitted nor denied by best guess record for domain of tom@honermann.net) smtp.mailfrom=tom@honermann.net Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:29470 Archived-At: On 11/18/2016 11:30 AM, col3435 via ISO C++ Standard - Future Proposals wrote: > How about allowing literal types as template arguments if they have > defaulted == and != operators (and this condition also applies recursively > to all of their members). It does look fairly likely that we will get > default == > in the language in the near future. Once we have that, it would provide > a natural way to express which types are unproblematic for use as > template arguments. > > This would be more than good enough to get us arrays of characters. For mangling purposes, I would expect a more strict requirement to be necessary. Probably that all non-static data members are types (or arrays thereof) that are acceptable as non-type template arguments. Note that literal types include void, so, unless the regular void proposal is accepted, I think a term other than "literal type" is needed to describe the acceptable types here. Tom. -- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an email to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. To view this discussion on the web visit https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/4e5c0e7e-74c1-1983-ad27-0baede6ebe0a%40honermann.net. .